Pyxis dissolved oxygen sensor

Pyxis ST-773

An inexpensive optical luminescent dissolved oxygen (DO) sensor, made of CPVC, designed for inline or submersion installations.

The Pyxis Lab® ST-773 optical luminescent dissolved oxygen sensor is based on the principle of ‘fluorescence quenching’ to determine the dissolved oxygen content in water. It incorporates our advanced technology in the field of fluorescence detection and uses dual blue/red light detection technology with excitation and reference light sources, offering a wide detection range and very low detection limit.


  • 0.004–20mg/L measurement range – stable measurement with ultra-low drift
  • Simple PTFE film DO cartridge replacement
  • Built-in temperature sensor with automatic compensation
  • Built-in transmitter without preamplifier or meter head
  • Dual outputs both 4-20mA isolated signal & RS-485 modbus
  • CPVC body – lightweight & corrosion resistant
  • Wireless calibration, diagnostics, data trend via uPyxis® with the MA-WB
  • Submersible or inline installations available using our submersion or inline adapters
  • Meter tail = 3/4inch NPT outer diameter threading for simple installation


Typical applications

  • Activated sludge / aeration basin / nutrient removal
  • Wastewater
  • Chemical / process water applications
  • Domestic / drinking water applications
  • Filtration applications
  • Aquaculture
  • Agriculture

Product information

Related products

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  • Galvanic dissolved oxygen
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Custom build solutions

Redefine simplicity and flexibility in cooling tower solutions with our plug-and-play service that delivers rapid installation.

We offer standard layout that serves as a solid foundation but we can be customise to meet the unique needs of any client site. We tailor the build to achieve optimal performance.

Our custom builds are popular as a comprehensive solution that's wired and seamlessly integrated meeting any site requirements. Email us today to learn more about our bespoke custom built solutions to speed up your installation and reduce operation or project downtime.


We specialise in delivering tailored product training to empower your team and enhance operational efficiency. Whether you prefer on-site sessions, at your company's location or the convenience of video conferencing, we've got you covered.

Our focus revolves around installation best practices, ensuring seamless product connectivity, and optimising maintenance procedures. Take the first step towards maximising your team's potential. Email us today to learn more about our bespoke training offerings, check availability, and embark on a journey to enhance your team's expertise.

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Sensys Ltd

Head Office
24 Vision Park
Preston Place
Upper Caldecote
SG18 9GQ

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01438 759 595

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